I accidentally entered the London congestion charge zone while driving a hire car. When I received the penalty notice from the hire company I paid the £60 promptly online and received a receipt.

Later, a letter arrived from Transport for London which I scanned and put aside since I had paid the fine. I then received another letter, this one demanding £180. The wording was so confusing and unclear that I had to read it twice to work out what it was saying. Apparently, the first letter had told me I had been refunded my payment because liability had not yet been transferred to me from the hire firm. I sent another cheque for £60, but TfL insists I still owe £120. AH Dorset

The wording of the original letter is very opaque, especially since "This is not a penalty charge notice" is written in capitals across the middle, so you can be excused for assuming that you had nothing left to pay.

It is an equally opaque system that allows your hire company to bill you first, then for your payment to be refunded so that you can pay TfL direct. Transport for London explains that the hire company, as registered keeper of the vehicle, was initially held liable for the fine and that when it informed TfL that you were the driver it was legally bound to reissue the charge to you, even though you'd already paid.

Even TfL can see how daft this all sounds. The balance has been written off and the PCN closed.

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